High Blood Pressure Treatment (cont.)

John P. Cunha, DO, FACOEP

John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

Minoxidil

Minoxidil is the most potent of the
drugs that lower blood pressure by dilating the peripheral arteries. This drug does not work through the peripheral sympathetic nervous system as do
the alpha and beta blocker drugs, or through the control center in the brain, as
does clonidine. Rather, it is a muscle relaxant that works directly on the smooth muscle of the peripheral
arteries throughout the body. Minoxidil is used for patients who have not
responded to other medications. It must be combined with a beta blocker or
clonidine to prevent an increase in the heart rate and with a diuretic to
prevent retention of fluid (swelling). Minoxidil may also increase hair growth.

Renin inhibitors

Aliskiren (Tekturna) is in a class of antihypertensive drugs called renin inhibitors. Renin is an enzyme in the chain of blood pressure regulating hormones referred to as the renin-angiotensin-aldosterone (RAA) hormonal system.

The first step in the chain is the production of renin in the kidneys when the kidneys detect lower blood pressure. The renin stimulates the formation of a protein called angiotensin I, which is then converted to angiotensin II by angiotensin-converting enzyme (ACE) in the lungs, the same ACE targeted by ACE inhibitors. Angiotensin II is the most powerful constrictor of blood vessels known. This effect of constricting blood vessels tends to elevate the blood pressure. Angiotensin II also causes the secretion of an additional blood pressure elevating hormone in the adrenal glands called aldosterone, which helps the body retain sodium.

Aliskiren inhibits the effects of renin and angiotensin so that blood pressure does not go up.

Aliskiren should not be combined with ARB or ACE drugs in patients with diabetes because of the risk of renal impairment, hypotension, and hyperkalemia.